Chamber length

[Bruce Barletta]

How to tell or measure if your chamber has been lengthened? 12 ga. Gun was made with 2-1/2 chambers.

[Dean Romig]

What sort of documentation do you have that says it was made with 2 1/2" chambers?

What year was it made? What gauge is it? Do you have a letter on it? What were the results of Parker Bros. test firing it?






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[Bruce Barletta]

Made in 1908,,,12 ga.. bought used??? I cant remember what year they went to 2-3/4,, but this was made before that.....

[Dean Romig]

Have you measured the chamber depth with a precision instrument?






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[Wild Skies]

A precision measuring chamber gauge or even a machinist's scale is just the ticket for measuring your gun's chamber length. But, if you don't have either of those, a Po' Man's Chamber Gauge will do everything you need it to do.
http://parkerguns.org/forums/showthread.php?t=18161

[Researcher]

Generally speaking a 1908 vintage 12-gauge Parker Bros. double would have had 2 5/8 inch chambers, intended for 2 3/4 inch shells.

At that time, the U.S. ammunition manufacturers offered loaded 12-gauge paper shells in 2 5/8, 2 3/4, 2 7/8 and 3-inch lengths. In the 1890s and early 1900s you could get up to 1 1/4 ounce loads in any of these length 12-gauge shells, but between about 1905 and 1908 they phased out offering 1 1/4 ounce loads in the 2 5/8 inch shells. From then on they only offered up to 1 1/8 ounce loads in the 2 5/8 inch case and one had to go to the 2 3/4 inch or longer shells for 1 1/4 ounce of shot.

All of the repeating shotguns being introduced in those days were made for 12-gauge 2 3/4 inch shells -- Winchester Model 1897, Remington Autoloading Shotgun, Remington Repeating Shotgun, J. Stevens Arms & Tool Co. No. 520, etc.

[Bruce Day]

Parker chamber lengths from TPS:

[J.B. Books]

Originally Posted by Bruce Day

Parker chamber lengths from TPS:

8ga - 3 1/4" chambers for 3 1/4" shells.

10ga - 2 7/8" chambers for 2 7/8" shells.

12ga - 2 5/8" chambers for 2 3/4" shells.

Why the inconsistency?

[Dean Romig]

Originally Posted by Pete Lester

8ga - 3 1/4" chambers for 3 1/4" shells.

10ga - 2 7/8" chambers for 2 7/8" shells.

12ga - 2 5/8" chambers for 2 3/4" shells.

Why the inconsistency?

Were the 8 and 10 gauge chambers cut for brass shells or paper?

The 2 5/8" chambers were for 2 3/4" paper shells, allowing for 1/8" of the paper shell to open into the cone for a superior gas seal.






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[J.B. Books]

Originally Posted by Dean Romig

Were the 8 and 10 gauge chambers cut for brass shells or paper?

The 2 5/8" chambers were for 2 3/4" paper shells, allowing for 1/8" of the paper shell to open into the cone for a superior gas seal.


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I have owned 4 Short Tens, Parker, Remington, Lefever, from 1893 to 1905. The Parker from 1893 had square chambers, the others from 1900-1905 are tapered. All measured 2 7/8"

I still believe guns were chambered for a particular shell and marketing was used to tell the customer it could be used with another shell length and work just fine. I also think when it is difference of 1/8 inch collector/shooters fret too much about it in both directions (OMG my chambers are short, or OMG my chambers were lengthened). The focus should be on barrel wall thickness of each particular gun and shooting lower pressure loads when possible, but that is just me.